1. Field of the Invention
This invention is generally related to vehicle ignition locks and is directed to a rotatable ignition lock having an electrical interlock.
2. Description of the Prior Art
The development of numerous different electronic VATS systems for an automobile has taken place over the years. One such system incorporates the use of a resistor pellet in an ignition key. The pellet provides for a resistor of known value so that upon insertion and rotation of the key in the automobile's ignition cylinder an electric current is applied to the resistor. A decoder circuit performs a resistance comparison between the pellet in the key and a known resistance "window." If the resistance is within the window, the automobile may be started. If the resistance does not match, the automobile will not start.
Typically, a vehicle ignition lock includes a cylinder rotatable within a hollow sleeve both of which extend into the steering column of a vehicle. A bezel or end cap is attached to the outer end of the cylinder and is located on the exterior of the steering column. The bezel includes a key slot or key way adapted for receiving the ignition key. It has been found that the inside surface of the bezel between the bezel and the outer end of the cylinder is a convenient location for mounting the electrical contacts that engage the key resistor pellet which complete the resistor pellet circuit when the key is fully inserted in the key way.
In the prior art, the contacts were placed on a base and held in position by a cover. A wiring harness consisting of a pair of wires attached to the contacts for completing the electrical circuit extended through the cover and were carried down the vehicle steering column to a remote position in the vehicle. The prior art wiring harness and contact carrier comprised a pair of contacts mounted directly on the end of a pair of wires at the end of the harness. The wires and contacts were clamped into place by positioning the cover over the bezel. The cover and bezel were then secured to the outer end of the ignition lock cylinder.
A disadvantage of the prior art systems for mounting the contacts in the bezel was the failure to securely position the wires in place, potentially causing a fatigue failure at the contact crimp area. A further disadvantage to the prior art system is the way the wires are clamped between the cover and the base, permitting the wires to move relative to the base, further increasing instability and potentially causing wear points on the wires and a fatigue failure. Yet another disadvantage is the potential improper positioning of the wires during assembly, causing damaged, pinched or broken wires.